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(No Model.)

H. N. LOW.

ADJUSTABLBPIVOT JOINT.

Patented Aug. 28, 1883.

Wc'tneffef N. PETERS. Plmmuxrmgnpmr, wnhingm. D. C,

f NITED VSTATES Arana* Orricn.

ADJUSTABLE PIVOT-JOINT.

SPECIFICATION forming part 0f Lettls Patent NO. 283,907, dated August 28, 1883,

Application led May 3, 1883. (No model.)

To all whom) it may concern:

Be it known that I, HARRY N.'Low, a citizen of the United States, residing at Vashington, in the District of Columbia, have invented certain new and -useful Improvements in Adjustable Pivot-Joints for Drawing-Instruments, of which the following is a specification, reference being had therein to the accompanying drawings.

The object of my invention is to provide a joint for drawing-instruments, whereby two parts can be hinged or pivoted together at any desired point of their length. I am aware that a joint of the kind thus broadly described is old, but I have devised certainimprovements in its construction, whereby the parts are each held more securely in .their positions relative to the pivot, and, moreover, the friction between the pivoted parts when oscillated relative to one another is materially lessened. This joint is particularly useful in proportional `dividers, and I will illustrate and describe it as being applied thereto.

Figurelis a front elevation of a pair of proportional dividers. Fig. 2 is a vertical section on line x x. Fig. 3 is a cross-section, eni larged, on line y y. Fig. 4 is a similar section,

Ashowing further improvements in construction. Fig. 5 is a view showing some ofthe details of Fig. 4.

A A are the legs orrbars of the dividers, pointed at both ends, and having each a slot for substantially half their length, for the reception of the clamping devices and the passage ofthe pivot. The usual mode of construction heretofore used is to make the slot beveled or flaring outward and clamp the legs against one another by means of pieces which are reversely beveled to fit the slots and are drawn forcibly toward one another and againstthe slotted bars. rlhe legs are thus tightly pressed against one another, and when the clamp is tig-ht enough to prevent slipping along the slot a great deal of friction is encountered in opening or closing the legs, which operation is constantly necessary in their use. When so made the bars are also worn away unevenly on their faces which `come in contact. I have obviated these difficulties by placing the bearing-11 ieces B B between the pivoted bars and compressing the latter against them. The bearing-pieces being of such thicktact, or wear between the pivoted bars..

ness as to leave a small space between the side bars, and having a pivotal connection with one another, the friction takes place entirely between them, and there is no friction, con- The bars are made parallel with one another for such part of their length as the slot extends, and from that point approach one another until the points of the divider-bars at each end coincide with one another, (see Fig. 2,) this being necessary to their operating with the greatest accuracy. `By beveling the slots A A so that they nare inwardly, (see Fig. 3,) and beveling the bearing-pieces B B to fit the slot, the bars A A may be held more firmly in position and a longitudinal slipping pre vented. The bearing-pieces B B are of sufficient length to obtain a firm engagement with the bars A A. rIhe clamping is effected by means of engaging pieces or washers O C on the outside of bars A A, connected vby a bolt, E, and thumb-nut F. The bolt E may be relied upon to keep the pieces B B in axial line with one another, the inner surfaces of said pieces being perfectly plain, (see Fig. 3,) or preferably, as shown, a circular boss,I b, may be raised upon the surface of one and a corresponding rabbet or depression made in the surface of the other, into which the part b fits closely, thus forming a bearing of greater c'ir ference and trueness of center. (See Figs. 4 and 5.) The washers O C may be made with slight inward rectangular projections, which fit the slots A and` prevent rotation of the washers, thus adding to the firmness with which the legs are clamped, (see Figs. 2 and 3;) or a construction like Fig. 4i may be used, iii-which the slots A A of the legs A A have` a bevel flaring outwardly, which the washers O O are made to fit, and by means of which the washersa-re prevented from turning andI enabled to more securely clamp the legs to the pivot. The usual method of preventing the nut F from being turned and loosened by the movement of the legs is adopted, the bolt be- `ing squared in the washer against which the nut bears and turning in the clamping-pieces of the opposite leg.`

l. The herein-described adjustable vpivotjoint, consisting of the combination, with the slotted pivoted bars, of bearing-pieces pivot- IOO ally connected with one another and arranged between said bars toI prevent their contact, and devices engaging with `the bars, whereby they maybe compressed against the bearingpieces, substantially as set forth.-

2., The herein-described adjustable pivotjoint, consisting of the combination, with. the slotted pivoted bars, of bearing-pieces arranged between said bars to prevent their contact, a portion of one bearing-piece being let into the other to form a pivotal bearing, and devices engaging with the bars, whereby they mayr be compressed against the bearing-pieces,

substantially as set forth.

3. The herein-described adjustable pivot-i joint, consisting of the combination, with the pivoted bars having beveled slots flaring toward the opposing surfaces ofthe bars, of correspondingly-beveled bearing-pieces pivotally Y 2o connected with one another and arranged between said bars to prevent their contact, and devicesengaging with the bars, whereby they may be compressed against the bearing-pieces, substantially as set forth.,

4C. rlhe herein-described adjustable pivotjoint, consisting of the combination, with the pivoted bars having beveled slots flaring toward the opposing surfaces of the bars, of correspondingly-beveled bearing-pieces arranged 3c betweeny said bars to prevent their contact, a portion of one bearing-piece being let into the other to form a pivotal` bearing, and devices engaging with the bars, whereby they may be compressed against the bearing-pieces, sub- 3 5 stantially as set forth.

5. The herein-described adjustable pivotjoint, consisting of the combination, with the slotted pivoted bars, of bearing-pieces pivotally connected with one another and arrangedV 4o between said bars to prevent their contact, and pieces wider than .the narrowest part of the 4slots engaging with the outer portion of the bars and connected by a bolt and nut, whereby the bars may be compressed against the bearing-pieces, substantially as set forth.

6. The herein-described adjustable pivotjoint, consisting of the combination, with the slotted pivoted bars,'of'bearingpieces interposed between said bars to prevent their con- 5o tact, a portion of one bearing-piece being let into` the other to form a pivotal bearing, and pieces wider than the narrowest part of the slots engaging with the outer portion of the bars, and connected by a bolt and nut, whereby 5 5 the bars may be compressed against lthe bearing-pieces, substantially as set forth.

7 The herein-described adjustable pivotjoint, consisting of the combination, with the pivoted bars having beveled slots flaring to- 6 o ward the opposing surfaces of the bars, of correspondingly-beveled bearing-pieces having a pivotal connection with one another, and arranged between said bars to prevent their contact, and pieces wider than the narrowest part f the slots engaging with the outer portion of the bars, and connected by a bolt and nut, whereby the bars may be compressed against the bearing-pieces,substantially as set forth.

8. The herein-described adjustable pivotljoint, consisting of the combination, with the 7o pivoted bars having beveled slots iiaring toward the opposing surfaces of the bars, of correspondingly-beveled bearing-pieces interposed between said bars to prevent their contact, a portion of one bearing-piece'being vlet 75 into the otherto form a pivotal bearing, and ypieces wider than the narrowest partI of the slots engaging with the outer portion of the bars, andconnected by a bolt and nut, whereby the bars may be compressed against the 8o bearing-pieces, substantially as set forth.

9. The herein-described adjustable pivotjoint, consisting of the combination, with the slotted pivoted bars, of bearing-pieces pivotally connected with one another and arranged between said bars to prevent their contact, and pieces beveled and seated in an outwardly-flaring portion of the slot, and connected by a bolt and nut, whereby the bars may be compressed against the bearing-pieces, sub- 9o stantially as set forth. I

10. rlhe herein-described adjustable pivotjoint, consisting of the combination of the slotted pivoted bars, of bearing-pieces interposed between said bars to prevent their contact, a 9 5 portion of one bearing-piece being let into the other to form a pivotal bearing, and pieces beveled and seated in an outwardly-flaring portion of the slot, and connected by a bolt and nut, whereby the bars may be compressed roo against the bearing-pieces, substantially as set forth.

ll. The herein-described adjustable pivotjoint, consisting of the combination, with the pivoted bars having beveled slots flaring toward the opposing surfaces of the bars, of correspondingly-beveled bearing-pieces having a pivotal connection with one another, and arranged between said bars to prevent their contact, and pieces beveled and seated in an 1 1o outwardly-flaring portionv of the slot, and connected by a bolt and nut, whereby the bars may be compressed against the bearing-pieces, substantially as set forth.

12. The herein-described adjustable pivotv joint, consisting of the combination, with the pivoted bars having beveled slots flaring toward the opposing surfaces of the bars, of correspondingly -beveled bearing-pieces arranged between said bars to prevent their con- 12ok tact, a portion of one bearing-piece being let into the other to form a pivotal bearing, and pieces beveled and seated in an outwardlyflaring portion of the slot, and connected by a bolt and nut, whereby the bars may be comr2 5 pressed against the bearing-pieces, substantially as set forth.

13. The herein-described adjustable pivotjoint, consisting of the combination of the slotted pivoted bars, arranged parallel to and rg0 at a slight distance from one another for that portion of their length which is occupied by the slots, and coinciding with one another at their points, of bearing-pieces pivotally conalso circular, and concentric with the pivot, within which recess the said raised portion fits closely to form a pivotal bearing, substantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

HARRY N. LOW.

Witnesses:

J. S. BARKER, L. H. MARSHALL. 

